Selector valve means for dental units



y 2, 1970 J. D. KRANTZ 3,511,264

SELECTOR VALVE MEANS FOR DENTAL UNITS Filed March 20, 1968 i AIR SOURCE FOG SPRAY FOG SPRAY WATER AIR WATER SOURCE I aulllll 63 Vii w P r INVENTOR.

JOHN DANIEL KRANTZ CYfioZZ'a adzal' w ATTORNEYS United States Patent r U.S. Cl. 137-35518 8 Claims ABSTRACT OF THE DISCLOSURE A selector valve in the form of an integral block construction is provided for controlling the passage of drive air, water, and chip air to a suitable hand piece used by a dentist during treatment of a patient. The block itself includes first, second and third inlet passages for connection to sources of drive air, water, and chip air respectively, and first, second, and third outlet passages for connection to suitable outlets in a hand piece through the medium of a retractable hose mechanism. The drive air may be used to drive a dental drill, for example, the water and chip air combined to provide a fog spray in the hand piece, and the chip air alone for blowing away small chips or debris in a treated area in the patients mouth. The selector block also includes first, second, and third valve bodies having extending stem portions engaged by the retractable hose mechanism when in retracted position to hold the valves in first positions closing off communication between the inlet passages and outlet passages in the block. Withdrawing of the retractable hose means frees the valve stems so that the valve bodies can move to second positions placing the inlet passages in communication with the. outlet passages, the valve bodies themselves being moved by the air, water, and chip air pressures respectively. Drive air, water, and chip air are thus available in the dental hand piece at the free end of the retractable hose means automatically in response to withdrawing of the hose.

This invention relates generally to dental equipment and more particularly to a novel selector valve block structure for control of water and air delivered to a hand piece in a dental unit.

In dentistry equipment, there is available a source of air under pressure and a source of water under pressure. The air pressure is normally utilized to operate high powered dental drills and the like and for purposes of the present case, such air source will be referred to as drive air. In addition, it is often desirable to provide a fog spray or mist for cleaning out areas in the mouth and teeth during a drilling operation and towards this end, water and an additional air supply is necessary. Towards this end, such water supply is hereinafter referred to as simply water and such air supply is hereinafter referred to as chip air. Combining the water and chip air in a suitable hand piece will provide the desired fog spray or mist. Finally, it is desirable to provide a strong air fioW from the hand piece without any water mixed therein to blow away collected debris. This latter air is hereinafter referred to as chip air.

The provision of drive air, water, and chip air has heretofore necessitated the presence of various different 3,511,264 Patented May 12, 1970 types of valves and controls therefor which constitute a large part of the components involved in dental units. In many instances, the valves are electrically controlled and such systems, of course, require the presence of suitable electrical circuitry and electrical sources. In the provision of modernized dental equipment, it would be very desirable to minimize the number of components such as valves and the like and yet enable the desired above functions to be carried out.

In applicants co-pending patent application Ser. No. 659,172, filed Aug. 8, 1967 and entitled Latch Structure for Pull Lines there is described an improved retractable hose means and latch structure particularly well suited to portable type dental equipment. The, provision of retractable hoses or tubes is desirable in that the exterior obstructions are minimized and for any particular operation, a single hose structure need only be withdrawn from the unit and utilized with an appropriate hand piece. In keeping with the concept of portability and compactness, it is desirable to provide in at least one of the retractable hose mechanisms a supply of drive air, water, and chip air respectively. There is thus required a suitable valve structure cooperating with the retractable hose mechanism to make available these sources of fluid.

With all of the foregoing considerations in mind, it is a primary object of the present invention to provide a novel selector valve structure particularly adapted for cooperation with the retractable, hose mechanism of a dental unit wherein drive air, water, and chip air can be made readily available at the free end of the retractable hose mechanism for use in a hand piece and yet wherein the number of auxiliary components and valving is minimized all to the end that a compact and integral structure with minimum parts results for performing functions heretofore requiring the provision of several separate valves.

More particularly, it is an object to provide a novel selector valve block which is operable to open positions by means of the presence of fluid pressure itself either from water or air and which is caused to automatically close by the retractable hose mechanism to the end again of minimizing a number of auxiliary parts heretofore deemed necessary.

Still another important object of this invention is to provide a novel selector block structure designed for use in cooperation with additional similarly constructed selector block valves in a manner such that a single pressure monitoring gauge may sufiice for indicating conditions in any one particular selector block valve being utilized. I

Briefly, these and many other objects and advantages of this invention are attained by providing an integral block constituting the selector valve. This block is provided with first, second, and third inlet passages in one face for connection to first, second, and third sources of drive air, water, and chip air respectively. The block also includes first, second, and third outlet passages in another face for connection to suitable drive air, water, and chip air outlets in the free end of a retractable. hose means.

The integral block also includes first, second, and third valve bodies movable within the block between first positions in which the inlet and outlet passages are blocked from communication with each other and second positions in which the inlet and outlet passages are placed into communication with each other. These valve bodies include valve Stems projecting from a face of the integral block structure in positions to be held or urged inwardly into the block by the retractable hose mechanism when in its retracted position. In their inwardmost position, the stems hold the valve bodies in their first or closed positions so that there is no communication between the inlet and outlet passages. When the hose retracting mechanism is withdrawn, the stems are freed so that the valves may move to their second positions in response to the presence of air or water pressure as the case may be.

Suitable connecting and transverse passages within the integral block structure provide means for controlling the drive air pressure and also indicating or monitoring the same. The arrangement is such that when more than one selector block valve structure is employed in a dental unit, proper monitoring of drive air supplied to additional selector block valves can be effected by a single pressure gauge.

A better understanding of the invention and its various features and advantages will be had by now referring to a preferred embodiment thereof as illustrated in the accompanying drawings, in which:

FIG. 1 is a schematic perspective view showing a selector block valve mechanism positioned for cooperation with a retractable hose mechanism in accord with certain teachings of the present invention; and,

FIG. 2 is an enlarged divided or broken view of the integral selector block valve of FIG. 1 for exposing interior portions thereof useful in explaining the operation of the valve.

Referring first to FIG. 1 there is indicated by the horizontal dashed lines in the upper right hand portion of the drawing suitable guide tracks for a retractable hose means. In this respect, the retractable hose means and guide track may be similar to that shown and described in my earlier mentioned co-pending application. As shown in FIG. 1, this mechanism includes a supporting bracket 11 having a forward portion 11a rotatably mounting a pulley 12, a central portion 11b bent to extend rearwardly of the pulley, and a guide track cooperating portion 110. The arrangement is such that the portion 11c may glide or slide in the track 10 from left to right as viewed in FIG. 1.

At the far right hand portion of the structure, there is provided a return pulley 13. A retractable hose 14 includes a free end 15 arranged to be mounted to the exterior of a dental unit housing for manual pulling or withdrawing from the dental unit. The hose 14, as shown, loops about the pulley 12 and thence about the return pulley 13 to terminate at its other end in a fixed anchor structure 16 within the dental unit. It will be evident that by pulling on the free end 15 of the hose in the direction of the arrow 17, the pulley 12 will be caused to move along the guide track 10. A suitable latch mechanism (not shown) such as described in the heretofore referred to copending application may be provided to hold the hose in an extended position.

Release of the latch mechanism will permit retraction of the hose within the unit as by means of a suitable spring schematically indicated at 18 to the extreme left of FIG. 1. In FIG. 1, the supporting bracket 11 and pulley 12 are not shown in their completely retracted position but rather in the position they would appear after a small initial withdrawing movement of the hose.

Referring now to the upper left portion of FIG. 1, there is illustrated a selector valve in the form of an integral block 19. A closure plate 20 is pivoted to opposite sides of the block 19 at 21 for downward swinging movement in a direction to engage first, second, and third valve stems 22, 23, and 24. The positioning of the selector block 19 and closure plate 20 is such that the outer surface of the closure plate will be engaged by the intermediate portion 11b of the retractable hose mechanism bracket 11 when the pulley 12 is in its fully retracted position; that is, sutficiently further to the left as illustrated in FIG. 1 to engage the plate 20. The biasing spring 18 for the retracting mechanism thus exerts a pressure on the plate 20 which will urge simultaneously all three of the valve stems 22, 23, and 24 into the front face 25 of the selector block 19. When the hose is withdrawn to pull the pulley 12 and bracket structure 11 to the right, the valve stems will be free to move outwardy from the front face 25 of the selector block.

The block 19 includes first, second, and third inlet passage fittings 26, 27, and 28 on the face 29 opposite the front face 25. Also shown exposed on the rear face 29 is a screw adjustment 30, the purpose for which will become clearer as the description proceeds. Additional inlet fittings are provided at 31 and 32 for cooperation with an air pressure gauge 33. The manner in which these components function will also become clearer as the description proceeds.

The exterior of the selector block structure is completed by first, second, and third outlet passage fittings 34, 35, and 36 arranged to connected to suitable line passing through the hose 14 to suitable outlets 34, 35, and 36' respectively at the free end of the hose 14. As indicated by the lettering, these three outlets serve to supply air, water, and chip air for use with a suitable hand piece (not shown).

Referring now to the lower central portion of FIG. 1, there is indicated an air pressure source 37 connecting to a control means including a foot valve 38 having a drive air line 39 connecting to the first inlet passage fitting 26 for the selector block 19. A water source 40 provides water to a fog spray water control 41 interconnected with the foot valve 38 as indicated by the line 42 and having a fog spray water outlet 43 connecting to the foot valve 38 and thence through a water line 44 connected to the second inlet passage fitting 27 in the selector block 19. A fog spray air control 45 also interconnected with the foot valve 38 as indicated at 46 provides chip air through a chip air line 47 connecting to the third inlet passage fitting 28 in the selector block.

The foot valve 38 constitutes a three position valve for supplying drive air, water, and chip air through the lines 39, 44, and 47 to the first, second, and third inlet fittings in the selector valve. The selector valve block 19 itself functions to interconnect the various inlets with the outlet passage fittings 34, 35, and 36 when the various valve stems 22, 23, and 24 are free to move outwardly from the block 19; that is, when the retraction hose means is withdrawn to free the closure plate 20.

Referring now to the fragmentary exploded view of FIG. 2, details of the interior of the selector block valve 19 will become evident. As shown at the lower left of FIG. 2, the first inlet passage fitting 26 provides communication between the drive air inlet line 39 and a first inlet passage 48 in the block. A vertical connecting passage 49 in turn connects to a first outlet passage 50 receiving the outlet fitting 34. A first guide bore 51 slidably supporting a first valve body 52 communicates with the inlet passage 48 and outlet passage 50 through the connecting passage 49. The valve body 52 is formed with the stem 22 referred to in FIG. 1 so that the position of the valve body 52 in the guide bore 51 is controlled by movement of the stem. In the position shown in FIG. 2, the inlet passage 48 is cut off from communication with the guide bore 51 and thus is blocked from communication with the outlet passage 50. In this position of the valve body 52, the first valve stem 22 is in its inwardmost position in the block; that is, the position it would assume when the retraction mechanism described in FIG. 1 is in its completely retracted position to bear against the closure plate 20.

The connecting passage 49 is laterally intercepted by a bore 53 incorporating the adjusting screw 30. The arrangement is such that the effective cross-sectional area of the connecting passage 49 may be varied by the adjustment screw 30 to thereby control the rate of flow of air through the passage 49.

The first block section also includes a shuttle type check valve member 54 slidable in an air pressure inlet cavity 55 receiving the fitting 31. Adjacent to this check valve is a transverse passage 56 which extends transversely through the block structure a substantial distance to terminate in an air pressure gauge outlet passage or chamber 57 in the far exploded block section. This passage 57 connects through the air pressure gauge fitting 32 to the air gauge 33 described in FIG. 1. The check valve 54 is movable from a first position which closes off the inlet through the fitting 31 and places the transverse passage 56 in communication with the outlet passage 50 to a second position in which the communication between the outlet passage 50 and transverse passage 56 is blocked and the transverse passage 56 is placed in communication with the inlet through the fitting 31.

Referring now to the center section of the exploded block structure, there is illustrated at 58 the second inlet passage. This passage is arranged to communicate through a connecting passage 59 to the second outlet passage shown at 60. Again there is provided a second guide bore 61 receiving a second valve body 62 connecting to the stem 23 and movable between positions in which the inlet passage 58 is blocked from communication with the outlet passage 60 to a position in which these inlets and outlets are placed in communication.

The third block section illustrated in FIG. 2 includes a third inlet passage 63, connecting passage 64 and a third outlet passage 65. A third guide bore 66 supports a third valve body 67 for movement between first and second positions to effect blocking and opening of communication between the inlet and outlet passages.

In the illustration of FIG. 2, the three valve bodies are shown in their first or closed position so that communication is blocked between the respective inlet passages and outlet passages. This situation obtains, as mentioned, when the retracting mechanism is in its fully retracted position.

The operation of the selector valve mechanism in conjunction with the retraction mechanism will now be described.

Referring once again to FIG. 1, assume that the retraction bracket 11 is retracted to its full position such that the closure plate 20 is pivoted downwardly to urge all of the valve stems 22 and 23 and 24 to their innermost positions within the block 19. The retraction spring 18 exerts sufiicient tension to hold the pressure plate in this position as long as the mechanism is retracted. The valve bodies 52, 62, and 67 described in FIG. 2 will then be in the positions shown and it will be evident that drive air, water, and chip air if available at the inlet passages will be blocked from communicating with the outlet passages 50 and 60 and 65.

If now a dentist wishes to drill, he will pull on the hose 14 to withdraw the retraction mechanism. This action will release the closure plate 20 but the valve bodies will stay in their initial positions until such time as drive air, water, or chip air pressure is available in the various inlet passages. The foot valve control 38 is actuated by the dentist in accord with the desired function. Thus to effect a drilling operation, only drive air is necessary and towards this end the foot valve is moved to a first position to pass drive air up through the drive air line 39 to the inlet fitting 26 in FIG. 1. The presence of this drive air in the inlet passage 48, as shown in FIG. 2, will cause the valve body 52 to be moved to the right to extend the stem 22. In other words, actuation of the valve body is effected by the air pressure of the drive air. The drive air is thus free to pass up through the connecting passage 49 to the outlet passage 50. The rate of air flow is preadjusted as described by means of the adjusting screw 30. The presence of the drive air in the outlet passage 50 will cause the check valve 54 to move to the left as viewed in FIG. 2 to close off the opening in the inlet fitting 31 and place the transverse passage 56 in communication with the outlet passage 50. Drive air pressure is thus communicated through the transverse passage 56 to the chamber 57 in the third block section and thence through the fitting 32 to the pressure gauge 33 described in FIG. 1. The drive air in the outlet passage 50 also passes through the corresponding line in the hose 14 to the outlet 34' for driving a suitable drill in the associated hand piece (not shown).

It should be noted that the second and third valve bodies 62 and 66 are free to move and thus place the corresponding inlet passages for water and chip air in communication with the corresponding outlet passages 60 and 65. However, these valves will not be moved until such time as water and/or chip air is provided through the water and chip air inlet lines 44 and 47 of FIG. 1.

During a drilling operation, assume that the dentist now wishes to clean out the area by means of a fog spray mist. In this event, the dentist will operate the foot valve to a second position. In this second position, drive air will still be supplied to the first inlet passage 48 but in addition, air pressure will be communicated from the foot valve 38 to the fog spray water control 41 to provide water from the source 40 through the foot valve and onto line 44 to the second inlet passage 58 in the valve block.

Also, the second position of the foot valve is such as to pass air from the air source 37 to the fog spray air control 45 and chip air line 47 to the third inlet passage 63 in the block valve of FIG. 2. The pressure of the water and the chip air will cause the valve bodies 62 and 67 to be moved to the right as viewed in FIG. 2 such that the water and chip air may pass through the respective connecting passages 59 and 64 to the second and third outlet passages 60 and 65. This Water and chip air is thus available at the hand piece through the outlets 35' and 36' and will be suitably mixed to provide the desired fog spray mist.

If the dentist now desires just to have chip air, the foot control is moved to a third position wherein water on the inlet water line 44 is blocked so that only chip air will be available. In other words, the same air that is employed to provide the fog mist spray can be used as chip air by simply removing the water source from the selector block. It should be understood that the second valve body 62 for the water line will remain in its open position as long as the hose is in its withdrawn position. However, no further water will pass through the block since the position of the foot valve in its third set position is such as to cut off this water flow.

When the dentist has completed the various operations with the hand piece in question, he can simply permit the spring 18 of FIG. 1 to retract the hose and at the completely retracted position, the intermediate portion 11b of the bracket structure for the retraction pulley 12 will engage the closure plate 20 and move all three valve stems 22, 23 and 24 into the front face 25 of the block thereby moving the valve bodies back to their original position shown in FIG. 2. In these positions, communication is thus closed off between the three inlet passages and three outlet passages.

In many dental units, there will be provided several hand pieces with corresponding retraction mechanisms. In this event, it is possible to use an identical selector block for the additional hand pieces and retraction mechanism. The blocks, however, are so designed that only one pressure gauge need be provided for indicating the pressure of drive air or other fluid in any one of the additional selector blocks as well as the particular selector block to which it is connected. Towards this end, the check valve 54 and inlet air pressure fitting 31 cooperate to provide communication between the fluid pressure in other associated selector blocks and the pressure gauge 33.

More particularly, and with reference once again FIG. 2, assume that the selector block shown is not being used but rather an associated selector block. T he corresponding pressure gauge outlet fitting for the other selector block corresponding to the fitting 32 in the selector block shown, would be connected by a suitable conduit directly to the inlet fitting 31. Air pressure would thus pass into the inlet fitting 31 to move the check valve 54 to the right as viewed in FIG. 2 thereby blocking communication between the outlet passage 50 and the transverse passage 56. However, this inlet air in the fitting 31 would then be able to pass through the transverse passage 56 to the chamber 57 and thence to the pressure gauge 33 which would now register the pressure of the air in the other selector block. It will be evident that as many selector blocks as desired may be arranged in tandem in the foregoing described manner.

From the foregoing description, it will thus be evident that the present invention has provided a novel selector block valve structure wherein many components heretofore deemed necessary have been elminated and yet the various desirable functions can readily be carried out. Further, it will be evident that the valves are all controlled by the pressure of the fluids involved themselves so that electrical controls and the like are unnecessary. Finally, the unique combination of the protruding valve stems in conjunction with the retraction mechanism permits position of the selector block valve in a concealed position in the unit to the rear of the retraction mechanism so that the face panel of the dental unit can be kept clear of various valve assemblies with the overall result of a compact and neat appearing design.

While the three fluid mediums for the selector block valve have been described as drive air, water, and chip air, it will be understood by those skilled in the art that other fluid mediums may be controlled by a selector block designed in accord with the teaching of the present invention. These names as used herein are merely for convenient designation of the fluids involved in describing the preferred embodiment.

What is claimed is:

1. A selector valve means for passing drive air, water, and chip air respectively from first, second, and third sources to drive air, water, and chip air outlets, comprising: an integral block having first, second, and third inlet passages in one face for connection to said first, second, and third sources respectively; first, second, and third outlet passages in another face for connection to said drive air, water, and chip air outlets respectively; and first, second, and third valve bodies movable within said block between first positions in which said inlet and outlet passages are blocked from communication with each other and second positions in which said inlet and outlet passages are placed into communication with each other, said valves having stems extending from said block; removable means normally holding said stems against outward movement to hold said valve bodies in said first positions, said valve bodies being responsive to the pressure exerted by said drive air, water, and chip air to move from their first to their second positions, respectively, automatically only when their corresponding stems are free to move outwardly from said block.

2. The subject matter of claim 1, including a retractable hose means incorporating said drive air, water, and chip air outlets, said retractable hose means being physically positioned to hold said removable means against said stems when said retractable hose means is in retracted position and free said stem of said removable means for outward movement when said retractable hose means is in withdrawn position.

3. In a dental unit including a control means for providing under pressure in first, second, and third lines, drive air, water, and chip air respectively; and a retractable hose means including a drive air outlet, a water outlet, and a chip air outlet, the improvement comprising: a selector valve means in the form of an integral block having first,

second, and third guide bores slidably receiving first, second, and third valve bodies respectievly, said bodies each having an axially extending stem projecting normally from one face of said block in a position to be urged inwardly by said retractable hose means when retracted to its full retracted position, said block including first, second, and third inlet passages for connection to said first, second, and third lines respectively, and communicating with said first, second, and third guide bores respectievly, and said block including first, second, and third outlet pasages for connection to said drive air, water, and chip air outlets in said hose retracting means respectively, and communicating with said first, second, and third guide bores respectievly, said valve bodies blocking communication between said inlet and outlet passages respectively when said stems are urged inwardly, said valve bodies being movable by drive air, water, and chip air pressure respectively to move in said guide bores to positions placing said inlet pasages in comunication with said outlet passage when said retractable hose means is withdrawn to a position permitting outward movements of said stems, whereby drive air, water, and chip air are automatically available at the free end of said retractable hose means in response to withdrawing of said retractable hose means.

4. The subject matter of claim 3, in which said integral block includes a connecting passage between said first guide bore and said first outlet passage; and an adjustment screw extending laterally into said connecting passage for varying the effective crosssectional area of said passage, whereby the rate of drive air flow at said outlet in said free end of said retractable hose means may be preestablished.

5. The subject matter of claim 3, in which said integral block includes an air presure gauge connecting passage extending from a face opposite said one face; and a transverse passage connecting said first outlet passage with said gauge connecting passage whereby the pressure of said drive air may be indicated.

6. The subject matter of claim 5, in which said integral block includes an air pressure inlet bore communicating with said transverse passage; and a check valve in said first outlet passage closing off communication between said air presure inlet bore and transverse passage when said first valve body is in open position and opening up communication between said air pressure inlet passage and said transverse bore when said first valve body is in closed position and simultaneously closing off communication between said first outlet passage and said transverse bore, whereby drive air pressure from the air pressure gauge connecting passage of another selector block valve identical to said first mentioned selector block valve may be passed to said air pressure inlet passage and through said transverse passage to a presure gauge associated with said first mentioned selector block valve such that a single gauge may be used to indicate the drive air pressure in more than one selector block valve.

7. The subject matter of claim 3, in which said control means includes a three-way foot valve control, a fog spray water control, and a fog spray air control, said foot valve control being connected to receive air under pressure from an air source and said fog spray water control being connected to receive water under pressure from a water source; and means interconnecting said fog spray water control with said foot valve control and said fog spray air control with said foot valve control such that operation of said foot valve control to a first position supplies drive air only to said drive air line, operation of said foot valve control to a second position supplies in addition to drive air to said drive air line both water and chip air to said water and chip air lines to thereby provide both water and chip air simultaneously at the water and chip air outlets at the free end of said retractable hose means for enabling the generation of a fog spray, and operation of said foot valve control to a third position results in shutting off of said drive air and water in said References Cited drive air and water lines and supplies chip air only to said UNITED STATES P ATENTS chip air line.

8. The subject matter of claim 3, in which said guide bores are parallel so that said stems extend from said one 5 face in parallel alignment; and a closure plate pivoted to FOREIGN PATENTS said block in a position to engage the ends of said stems 799,228 8/1958 Great Britain.

when swung inwardly towards said one face, said retractable hose means engaging said closure plate when in its re- DORSEY NEWTON Primary Examiner tracted position to hold said stems in their inward posi- 10 US, Cl, X R tions. 137-609 

